Revenue - Disaggregation of Revenue (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Disaggregation of Revenue [Line Items]
Revenue	$ 116,385	$ 103,564	$ 108,942
Operating Segments | Cable Communications
Disaggregation of Revenue [Line Items]
Revenue	64,328	60,051	58,082
Operating Segments | Cable Communications | Residential, Broadband
Disaggregation of Revenue [Line Items]
Revenue	22,979	20,599	18,752
Operating Segments | Cable Communications | Residential, Video
Disaggregation of Revenue [Line Items]
Revenue	22,079	21,937	22,270
Operating Segments | Cable Communications | Residential, Voice
Disaggregation of Revenue [Line Items]
Revenue	3,417	3,532	3,879
Operating Segments | Cable Communications | Residential, Wireless
Disaggregation of Revenue [Line Items]
Revenue	2,380	1,574	1,167
Operating Segments | Cable Communications | Business services
Disaggregation of Revenue [Line Items]
Revenue	8,933	8,191	7,795
Operating Segments | Cable Communications | Advertising
Disaggregation of Revenue [Line Items]
Revenue	2,820	2,594	2,465
Operating Segments | Cable Communications | Other
Disaggregation of Revenue [Line Items]
Revenue	1,719	1,624	1,754
Operating Segments | NBCUniversal
Disaggregation of Revenue [Line Items]
Revenue	34,319	27,211	33,958
Operating Segments | Media
Disaggregation of Revenue [Line Items]
Revenue	22,780	18,936	19,947
Operating Segments | Media | Advertising
Disaggregation of Revenue [Line Items]
Revenue	10,291	8,296	9,267
Operating Segments | Media | Other
Disaggregation of Revenue [Line Items]
Revenue	2,040	1,845	1,793
Operating Segments | Media | Distribution
Disaggregation of Revenue [Line Items]
Revenue	10,449	8,795	8,887
Operating Segments | Studios
Disaggregation of Revenue [Line Items]
Revenue	9,449	8,134	9,352
Operating Segments | Studios | Content licensing
Disaggregation of Revenue [Line Items]
Revenue	7,565	6,557	6,373
Operating Segments | Studios | Theatrical
Disaggregation of Revenue [Line Items]
Revenue	691	418	1,469
Operating Segments | Studios | Home Entertainment and Other
Disaggregation of Revenue [Line Items]
Revenue	1,193	1,159	1,510
Operating Segments | Theme Parks
Disaggregation of Revenue [Line Items]
Revenue	5,051	2,094	6,213
Operating Segments | Sky
Disaggregation of Revenue [Line Items]
Revenue	20,285	18,594	19,219
Operating Segments | Sky | Advertising
Disaggregation of Revenue [Line Items]
Revenue	2,489	1,998	2,249
Operating Segments | Sky | Direct-to-consumer
Disaggregation of Revenue [Line Items]
Revenue	16,455	15,223	15,538
Operating Segments | Sky | Content
Disaggregation of Revenue [Line Items]
Revenue	1,341	1,373	1,432
Eliminations
Disaggregation of Revenue [Line Items]
Revenue	(3,008)	(2,540)	(2,650)
Eliminations | NBCUniversal
Disaggregation of Revenue [Line Items]
Revenue	(3,048)	(2,006)	(1,585)
Corporate and Other
Disaggregation of Revenue [Line Items]
Revenue	461	248	333
Corporate and Other | NBCUniversal
Disaggregation of Revenue [Line Items]
Revenue	$ 87	$ 53	$ 31